Coupling for coal feeding worms



July 16, 1946. -w. M. S CHWE ICKART 0 COUPLING FOR COAL FEEDING- WORMS Filed March 28, 1944- a L v Patented July 16, 1946 UNITED I STAT ES PATENT OFFICE 7 2,404,145. I coU-PLING-Fon-ooAL FEEDING worms- William M. Schweiokart, cleveianaohm Application March 28, 1944, Serial No. 528,451

3 Claims.

This invention relates generally to the stoker art and particularly to a coupling for coal feeding worms, ash conveying worms and shafting.

The main object of this invention is to produce an inexpensive and efficient form of coupling for joining the sections of coal feeding worms.

The second object is to construct a coupling of the class described which can be readily attached or detached in the field.

The third object is to construct a coupling which will reduce the possibility of wear and corrosion between the contact surfaces of the associated parts.

The fourth object is to provide a coupling which will have the required strength to resist torque in both directions and end thrust in both directions and yet will occupy a minimum of space.

I accomplish these objects in the manner set forth in the following specification as illustrated in the accompanying drawing, in which;

Fig. 1 is a longitudinal section through the coupling and the adjacent ends of a pair of worm sections.

Fig. 2 i a transverse section taken along the line 22 in Fig. l.

Fig. 3 is an enlarged end elevation of the plug member.

Fig. 4 is a longitudinal section through a modified form of the device.

Fig. 5 is a transverse section taken along the line 55 in Fig. 4.

Similar numbers of reference refer to the same or similar parts throughout the several views.

Referring in detail to the drawing, there is shown in Figs. 1 and 4 the ends II] and I I of a pair of coal worm sections whose projecting portions I2 and I3 are provided with right hand threads I2R and left hand threads I3L. The shaft ends I2 and I3 are drilled and tapered to approximately A5" to the inch forming the sockets I2-S and I3S fluted along the tapen with 90 degree angle flutings I2-F and I3F. For the sake of illustration, the flutings I2-F and I3--F are not shown past the end of the plug I4.

For th purpose of illustration only, it is stated that if the maximum diameter of the taper is A there would be approximatel 24 flutes I2F and I3F formed in the circumference thereof.

Fitting into the tapered recesses is a fluted plug I4 whose flutes I5 and I6 mate with the flutes I2-F and I3--F of the tapered recesses I I. The ends I2 and I3 are joined by the reversely threaded sleeve I8 whose exterior I9 may be smooth or knurled or flattened as desired, without departing from the spirit of this invention.

When joining a pair of worm ends Ill and II' it is desirable to coat the parts with a compound and thereb fill up all of the voids and prevent corrosion due to moisture or other corrosive elements in the material being conveyed by the worm. It will be observed that if the sleeve I8 is turned to draw the ends I0 and II together, the double tapered plug I4 is forcibly pressed into the openings I1 and the ends III and II are solidly united. Any excess compound will fill the space 20 between the ends I2 and I3. Obviously too great an excess would be objectionable as it would prevent a proper seating of the parts.

Should it be desiredto uncouple the ends I0 and I I, it is only necessary to turn the sleeve I8 in the opposite direction with relation to the ends I0 and II and they will be forced apart by. this action.

In the form of the device shown in Figs. 4 and 5, the worm shaft end 2 I is provided with a tongue 22'and the worm shaft end 23 is provided with a slot 24 to receive the tongu 22. In this form of the device, the worm shaft ends 2| and 23 are provided with threads 2IR and 23-L which receive the right and left hand threads I8T of the sleeve I8.

In the latter described form of the device, axial rigidity is sacrificed for a lowered manufacturing cost but the principle of the operation is identical in the two forms of the device.

It will be understood that while in Figs. 1 and 2 the pitch is not illustrated as being uniform between adjacent flights of the coupled worms, it is desirable to have them so, although it is not absolutel essential. While all the references have been directed toward the coupling of coal feeding worms, it will be appreciated that the same arrangement applie to any other form of conveying worm as well as shafting for machine parts wherein the installation and operating conditions are such as to render use of the ordinary forms of coupling undesirable.

While I have thus illustrated and described my invention, it must be understood that the proportions illustrated are only by way of example. Also the number and type of the flutes I5 and the degree of taper of the plug I4 are not critical.

I claim:

1. In a device of the class described, the combination of a pair of worm sections having their adjacent shaft ends oppositely threaded, said shaft ends having fluted, tapered recesses formed therein along the worm axis, a double tapered plug having its largestdiameter knurled in the middle of its length and having flutes along its tapered surfaces adapted to mate with those in the shaft recesses and a threaded sleeve adapted to receive the threaded ends of said worm sections and draw same together upon said plug.

'2. A coupling for coal feeding worms consisting of a pair of externally threaded worm shaft ends having tapered recesses formed axially in the shaft ends and fluted longitudinally, a fluted nation of a pair of adjacent axially disposed shaft ends, each of which has a tapered recess formed therein, a tapered plug adapted to occupy both of said recesses when said shaft ends are drawn together, said plug and recesses having mating'flutes'formed therein adapted to selec tively position said shaft ends in a rotary direction, said shaft ends being oppositely threaded and, a sleeve having opposite internal threads adapted-to, receive thethreaded shaft ends in a manner to draw the shaft'ends together when said sleeve is rotated in one direction, and force same apart when the sleeve is rotated in the op-- posite direction.

WILLIAM M. SCHWEICKART. 

